This is what ticks me off about airlines.
If the OP had some kind of situation where he had to move his flight by half a day, the airline would charge him, either an arm and a leg if the flight was on a different day (and goodness, if he was going to leave at 10:50PM and intstead had to leave at 12:05AM that's a different day.), or perhaps just a couple of fingers if the same day.
But when they decide to change the flight, they just say "eh, so go when we tell you, or go p*** up a rope." Perhaps at the time he booked, AF had a promotion but maybe other airlines did too.
It's not like he's asking to change his departure airport from MUC to BKK.
I think they should bend over backwards to accomodate him. He bought a ticket in good faith. I'm not saying AF has to charter a plane just for him. But they should do anything reasonable and possible to make it good for him.
A few years ago my wife was flying YYZ-ATL-JAX and there was bad weather, they cancelled my wife's seat, it was at least partly their fault, as they did give her a $200 voucher. Everything the next day was sold out, and when I called them I just asked if they could rebook her the following day YYZ-ATL-MCO. They were very cooperative.